[KIS-2016-10] Concrete5 <= 5.7.3.1 (Application::dispatch) Local File Inclusion Vulnerability

[Egidio Romano <research@xxxxxxxxxxxxxxxxxxx>]

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Concrete5 <= 5.7.3.1 (Application::dispatch) Local File Inclusion Vulnerability
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[-] Software Link:

https://www.concrete5.org/


[-] Affected Versions:

Version 5.7.3.1 and probably other versions.


[-] Vulnerability Description:

The vulnerable code is located within the "Application::dispatch()" method:

326.    public function dispatch(Request $request)
327.    {
328.        if ($this->installed) {
329.            $response = $this->getEarlyDispatchResponse();
330.        }
331.        if (!isset($response)) {
332.            $collection = Route::getList();
333.            $context = new \Symfony\Component\Routing\RequestContext();
334.            $context->fromRequest($request);
335.            $matcher = new UrlMatcher($collection, $context);
336.            $path = rtrim($request->getPathInfo(), '/') . '/';
337.            try {
338.                $request->attributes->add($matcher->match($path));
339.                $matched = $matcher->match($path);
340.                $route = $collection->get($matched['_route']);
341.                Route::setRequest($request);
342.                $response = Route::execute($route, $matched);

The vulnerability exists because the path for the incoming request is retrieved 
using the
"Request::getPathInfo()" method from the Symfony framework, which allows to 
specify the path
for the request within some HTTP headers (like "X-Original-URL" and some 
others). So, it might
be possible to specify paths containing "dot-dot-slash" sequences without 
worrying about URL
encoding and path normalization done by the web server. This could be exploited 
by unauthenticated
attackers to include arbitrary .php files located outside the Concrete5 root 
directory or from the
Concrete5 codebase itself (potentially leading to unauthorized access to 
certain functionalities)
by sending an HTTP request like this:

GET /concrete5/index.php HTTP/1.1
Host: localhost
X-Original-Url: /tools/../../index
Connection: keep-alive

The dispatching process for this request will try to re-include the index.php 
file,
and this will end up with an unexpected error.


[-] Solution:

Update to a fixed version.


[-] Disclosure Timeline:

[05/05/2015] - Vulnerability details sent through HackerOne
[02/10/2015] - CVE number requested
[19/12/2015] - Vulnerability fixed on the GitHub repository
[26/06/2016] - Vulnerability publicly disclosed on HackerOne
[28/06/2016] - Publication of this advisory


[-] CVE Reference:

The Common Vulnerabilities and Exposures project (cve.mitre.org)
has not assigned a CVE identifier for this vulnerability.


[-] Credits:

Vulnerability discovered by Egidio Romano.


[-] Original Advisory:

http://karmainsecurity.com/KIS-2016-10


[-] Other References:

https://hackerone.com/reports/59665